Dual mode air screen refrigerator

ABSTRACT

A refrigerator operates in a single mode and a dual mode. A plurality of sides defines a storage compartment. At least one door provides access to the storage compartment via an opening in at least one of the sides. At least one outlet vent expels air across the at least one opening towards at least one inlet vent configured to receive at least a portion of the expelled air. A first cooling circuit is fluidly coupled to at least the storage compartment. A second cooling circuit is fluidly coupled to at least one of the outlet vent, the inlet vent, and at least one air screen inlet vent. The refrigerator operates in the single mode when the door is closed during which the first cooling circuit operates. The refrigerator operates in the dual mode when the door is open during which the first cooling circuit and the second cooling circuit operate.

BACKGROUND

The present application relates to refrigerators and freezers, typically of the commercial variety although the disclosed embodiments may be used for private/personal refrigerators.

The hospitality, catering, and institutional markets use and require refrigerators and freezers adapted to their unique operating environments. For example, these markets require a refrigerator with a large capacity and the ability to store not just fresh foods, but also prepared foods, including entire prepared meals. In addition, these refrigerators are often frequently opened and closed.

Unfortunately, opening a door on a refrigerator permits air at ambient temperature to enter a storage compartment of the refrigerator. This warmer air must then be cooled by the cooling system of the refrigerator to ensure that the interior temperature of the storage compartment remains sufficiently cool. Frequently opening the door increases the amount of ambient air that enters the refrigerator. To compensate, either the cooling system must work harder (e.g., longer and/or more frequently) and/or a larger cooling system must be employed. Both approaches significantly increases the energy consumed in order to maintain a desired internal temperature within the storage compartment.

In addition to a desire to use less energy, various industry goals and regulations require refrigerators to use less energy. Older refrigerators that relied upon simply running cooling systems longer, more frequently, or using larger cooling systems typically do not meet the new goals and regulations.

It is therefore desirable to provide a refrigerator capable of being used in a single mode and a dual mode that is more energy efficient than the prior art.

BRIEF SUMMARY

In one embodiment, a refrigerator includes a plurality of sides configured to define a storage compartment. There is at least one opening in at least one of the plurality of sides to provide access to the storage compartment. The opening is defined by a perimeter. At least one outlet vent and at least one inlet vent are set within the perimeter of the opening. At least one door is adapted to open and to close to provide access to the storage compartment via the at least one opening. A first cooling circuit includes at least a first compressor and is fluidly coupled to at least the storage compartment. A second cooling circuit includes at least a second compressor and is at least fluidly coupled to at least one of the at least one outlet vent and the at least one inlet vent. In some embodiments, the second cooling circuit draws cool air from within the storage compartment via an air screen inlet vent and expels the cool air through the at least one outlet vent. A door switch is configured to generate an open signal representative of an open state of the at least one door and a closed signal representative of a closed state of the at least one door. A controller is coupled to the door switch, the first cooling circuit, and the second cooling circuit. The controller is configured to (a) operate the first cooling circuit when the controller receives the closed signal and to (b) operate the first cooling circuit and the second cooling circuit when the controller receives the open signal.

Optionally, the refrigerator includes at least one temperature sensor coupled to the controller. The at least one temperature sensor is configured to generate a temperature signal representative of a temperature within the storage compartment and the controller is further configured to receive the temperature signal and to operate at least one of the first cooling circuit and the second cooling circuit in response to the temperature signal.

In another embodiment, a refrigerator is configured to operate in a single mode and in a dual mode. The refrigerator includes a plurality of sides configured to define a storage compartment. There is at least one opening in at least one of the plurality of sides to provide access to the storage compartment. At least one outlet vent is configured to expel air across the at least one opening towards at least one inlet vent configured to receive at least a portion of the expelled air. At least one door is adapted to open and to close to provide access to the storage compartment via the at least one opening. A first cooling circuit includes at least a first compressor, at least a first evaporator, and at least a first fan. The first cooling circuit is fluidly coupled to at least the storage compartment. A second cooling circuit includes at least a second compressor, at least a second evaporator, and at least a second fan. The second cooling circuit is at least fluidly coupled to at least one of the at least one outlet vent and the at least one inlet vent. In some embodiments, the second cooling circuit draws cool air from within the storage compartment via an air screen inlet vent and expels the cool air through the at least one outlet vent. The refrigerator is configured to (a) operate in the single mode when the at least one door is closed during which the first cooling circuit is configured to operate and to (b) operate in the dual mode when the at least one door is open during which the first cooling circuit and the second cooling circuit is configured to operate.

Methods of operating a refrigerator in a single mode and in a dual mode are also disclosed. The methods include obtaining a refrigerator, operating the first cooling circuit in the single mode when the at least one door is closed, and operating the first cooling circuit and the second cooling circuit in the dual mode when the at least one door is open.

These and other advantages, as well as the invention itself, will become more easily understood in view of the attached drawings and apparent in the details of construction and operation as more fully described and claimed below. Moreover, it should be appreciated that several aspects of the invention can be used with other types of refrigerators, freezers, service over counter, or other kitchen, restaurant, sales, and other similar equipment.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front perspective view of an embodiment of a refrigerator.

FIG. 2 is a front perspective view of another embodiment of a refrigerator with portions of the sides cut away to illustrate internal components.

FIG. 3 is a front perspective view of another embodiment of a refrigerator with a closed door.

FIG. 4 is a front perspective view of the embodiment of the refrigerator in FIG. 3 with an open door.

FIG. 5 is a close-up view of an outlet vent of the embodiment of the refrigerator in FIG. 3.

FIG. 6 is a close-up view of a door switch of the embodiment of the refrigerator in FIG. 3.

FIG. 7 is a schematic view of an embodiment of a controller, first cooling circuit, and a second cooling circuit for use in a refrigerator.

DETAILED DESCRIPTION

The present invention will now be further described. In the following passages, different aspects of the embodiments of the invention are defined in more detail. Each aspect so defined may be combined with any other aspect or aspects unless clearly indicated to the contrary. In particular, any feature indicated as being preferred or advantageous may be combined with any other feature or features indicated as being preferred or advantageous.

Several terms used in the specification and claims have a meaning defined as follows.

Closed Solid or Solid means a refrigerator and/or the refrigerator's door or doors in which more than 75 percent of the outer surface area of all doors on the refrigerator are not transparent.

Closed Transparent means a refrigerator and/or the refrigerator's door or doors in which 25 percent or more of the outer surface area of all doors on the refrigerator are transparent.

Transparent means greater than or equal to 45 percent light transmittance, as determined in accordance with the ASTM Standard E 1084-86 (Reapproved 2009), (incorporated by reference in its entirety) at normal incidence and in the intended direction of viewing.

Door means a movable panel that separates the interior volume or storage compartment of a refrigerator from the ambient environment and is designed to facilitate access to the refrigerated space/storage compartment for the purpose of loading and unloading items. This includes hinged doors, sliding doors, and drawers. Stated differently, a door is adapted to open and to close to provide access to the storage compartment via an opening in the refrigerator.

Door angle means:

(1) For equipment with flat doors, the angle between a vertical line and the line formed by the plane of the door, when

the equipment is viewed in cross-section; and

(2) For equipment with curved doors, the angle formed between a vertical line and the straight line drawn by connecting the top and bottom points where the display area glass joins the cabinet, when the equipment is viewed in cross-section.

Horizontal Closed means a refrigerator with hinged or sliding doors and a door angle greater than or equal to 45°.

Vertical Closed means a refrigerator with hinged or sliding doors and a door angle less than 45°.

Integrated average temperature means the average temperature of all test package measurements, i.e., temperature measurements taken within the refrigerated space/storage compartment during an energy consumption test.

Operating temperature means the range of integrated average temperatures at which a self-contained commercial refrigeration unit (refrigerator) with a thermostat is capable of operating.

Volume typically refers to the geometric definition of the term. With respect to testing the energy consumption of a refrigerator, the volume of the storage compartment or refrigerated space is determined via the method set forth in Association of Home Appliance Manufacturers' publication HRF-1-2008 (“HRF-1-2008”), Energy and Internal Volume of Refrigerating Appliances including Errata to Energy and Internal Volume of Refrigerating Appliances, Correction Sheet issued Nov. 17, 2009, herein incorporated by reference.

The method for testing and calculating energy consumption are set forth in part in 10 C.F.R. §§ 431.61-431.66 (2016), including Appendices A and B, and in the Air-Conditioning, Heating and Refrigeration Institute's publication Standard 1200 (I-P)-2010 (“AHRI Standard 1200 (I-P)-2010”), 2010 Standard for Performance Rating of Commercial Refrigerated Display Merchandisers and Storage Cabinets, 2010, both of which herein incorporated by reference.

Turning to FIG. 1, a refrigerator 10 is illustrated. Although the application typically refers to refrigerator, freezers, combined refrigerator-freezers, and service over counter appliances are all encompassed by the term refrigerator. The refrigerator 10 is configured to operate in a single mode and in a dual mode in accordance with a selected condition, such as a door being open.

The refrigerator 10 includes a plurality of sides 15, which may include top, bottom, front, back, and side panels. The sides 15 are constructed of materials and in manners known in the art. The sides 15 may include various conduits, such as electrical wiring that may couple various sensors and other components; fluid conduits for circulating refrigerants (liquid or air); insulation; and other such components.

The sides 15 are configured to define a refrigerated space or storage compartment 20. The refrigerator 10 includes two separate storage compartments, although the refrigerator might include one or more than two storage compartments.

At least one opening 22 in the plurality of sides is configured to provide access to the storage compartment 20. The opening is defined by a perimeter 24. The perimeter 24 may be formed from part of the side 15 into which the opening 22 extends and/or a portion of the storage compartment 20.

The refrigerator 10 optionally includes a door 30 adapted to open and to close to provide access to the storage compartment 20 via the opening 22. Refrigerator 10 includes two doors to access the two separate storage compartments. In some embodiments, a single door may be provided to access two or more separate storage compartments. As with the sides 15, the door 30 is constructed of materials and in manners known in the art. The door 30 may include various conduits, such as electrical wiring that may couple various sensors and other components; fluid conduits for circulating refrigerants (liquid or air); insulation; and other such components.

Further, the door 30 may be solid, partially solid, or transparent, as defined above. For example, the door 30 may include one or more separate transparent or semi-transparent panels that permit a user to view the contents of the storage compartment 20 even though the door 30 may be closed.

In addition, the door 30 may be oriented vertically, horizontally, at an angle, curved, or other shapes and orientations to accommodate the shape of the refrigerator 10 and the plurality of sides 15. For example, rather than vertical doors 30 positioned and coupled to a front side 15 of the refrigerator 10, the doors may be horizontal and positioned and coupled to a top side. Likewise, while the doors 30 are rectangular in shape, the doors could be square, round, or any other conceivable shape.

The door 30 may include one or more variety of mechanical and electrical latches and/or locks to ensure that the door 30 remains closed as desired, such as mechanical latch 31.

The refrigerator 10 may include a door switch 234, seen in FIGS. 4 and 6 and as discussed below, configured to generate an open signal representative of an open state of the at least one door 30 and a closed signal representative of a closed state of the at least one door 30.

The refrigerator 10 may optionally include various controls 32 that permit a user to turn on and off the refrigerator, adjust the temperature of the storage compartment, lighting controls, controls for any air screen functions, any optional timers for the different functions, and other user-controlled functions and attributes.

The refrigerator 10 may also optionally include various ventilation grates 34 that permit airflow to various mechanical components, such as compressors, evaporators, and the like.

The refrigerator 10 also optionally includes wheels 36 or other similar components to permit a user to more easily transport or move the refrigerator 10 between desired locations.

FIG. 2 illustrates an embodiment of a refrigerator 110, which is similar in all respects to the refrigerator 10, therefore several common components are not discussed again. The refrigerator 110 includes a plurality of sides 115 and a door 130, along with the other components indicated in refrigerator 10 that are not labeled in FIG. 2.

The refrigerator 110 includes a first cooling circuit 140 that optionally includes at least a first compressor 142, at least a first condenser 144, at least a first evaporator 146, and at least one fan 148, as illustrated in cutaway view. The first cooling circuit 140 is fluidly coupled to at least the storage compartment, such as storage compartment 20 in FIG. 1.

The refrigerator 110 also includes a second cooling circuit 150 that optionally includes at least a second compressor 152, at least a second condenser 154, at least a first evaporator 156, and at least one fan 158 as illustrated in cutaway view. The second cooling circuit 150 is at least fluidly coupled to at least one outlet vent 260 and/or to the at least one inlet vent 270, which are illustrated in FIGS. 4 and 5 and which are discussed in greater detail below. In some embodiments, the second cooling circuit 150 draws cool air from within the storage compartment 120 via an optional air screen inlet vent 274—which is otherwise similar to the at least one inlet vent 270 but for being positioned within the storage compartment 220—and expels the cool air through the at least one outlet vent 260.

As illustrated in FIG. 2, at least one evaporator 146, 156 is optionally positioned on the top side of the plurality of sides 15 and at least one of the first compressor 142 and the second compressor 152 are positioned below the storage compartment. Of course, the components of the first cooling circuit 140 and the second cooling circuit 150 may be positioned at other locations external to, around, and/or within the plurality of sides and the storage compartment of the refrigerator.

The first cooling circuit 140 optionally may be on a completely separate circuit from the second cooling circuit 150, parallel to the second cooling circuit 150, or in series with second circuit 150. These circuits whether separate, parallel, or series, refer to both the electrical wiring/circuitry and the fluid conduits/fluid circuits.

Illustrated in FIG. 7 is an idealized schematic of an embodiment of a first cooling circuit 340 fluidly coupled to a storage compartment 320 and a second cooling circuit 350 fluidly coupled to at least one outlet vent 360 and/or to at least one inlet vent 370. The first and second cooling circuits 340, 350 are similar to the previously discussed cooling circuits. The first and second cooling circuits 340, 350 may be used in any embodiments of a refrigerator, including those embodiments illustrated in FIGS. 1-6.

The first and second cooling circuits 340, 350 are coupled to a controller 380. The controller 380 may be any type of chip, computer, or other controller, with a program or hardwiring to accomplish a specific task. The controller 380 is coupled to a door switch 334, similar to the door switch 234 discussed below, the first cooling circuit 340, and the second cooling circuit 350. The controller 380 is configured to (a) operate the first cooling circuit 340 when the controller 380 receives a closed signal from the door switch 334 and to (b) operate the first cooling circuit 340 and the second cooling circuit 350 when the controller 380 receives an open signal from the door switch 334. In other words, the controller 380 is configured to operate the first cooling circuit 340 in the single mode and to operate the first cooling circuit 340 and the second cooling circuit 350 in the dual mode. It should be understood that “operate” does not necessarily mean continuous operation. Rather, the controller 380 may operate the first cooling circuit 340 and the second cooling circuit 350 in accordance with a program, in response to a temperature signal, or other guideline, whether user selected or in accordance with an algorithm.

For example, when the door switch 334 signals that the door is closed, the controller 380 optionally would just operate the first cooling circuit 340, perhaps continuously, but also perhaps intermittently as required to maintain an interior temperature of the storage compartment 320. And while the door switch 334 signals the door is closed the second cooling circuit 350 would not be operated by the controller 380. Similarly, when the door switch 334 signaled that the door was open, the controller 380 could optionally operate both the first cooling circuit 340 and the second cooling circuit 350. The operation of the first cooling circuit 340 and the second cooling circuit 350 may both be simultaneous, alternating, one continuous and the other intermittent, or any other combination of operation. As one example, with the door open the controller 380 might operate the second cooling circuit 350 continuously, but only operate the first cooling circuit 340 intermittently as necessary to maintain a desired internal temperature within the storage compartment 320.

Optionally, the controller 380 is configured to wait a period of time after the controller 380 receives the open signal from the door switch 334 before the controller 380 operates the first cooling circuit 340 and/or the second cooling circuit 350. The period of time may be adjustable, whether manually by a user or by an algorithm in response to a selected criterion or criteria, and may extend from a milliseconds to seconds to minutes or longer. For example, once the door is opened, the controller 380 may delay operating the second cooling circuit 350 for a period of 5 seconds. Should the door be closed before the 5 seconds elapses the second cooling circuit may be capable of operating, but the controller in fact never actuates or employs the second cooling circuit 350. Should, however, the door remain open longer than 5 seconds, the controller may then operate or actuate the second cooling circuit 350 in order to establish an air screen proximate the opening of the refrigerator. In other embodiments the delay may be other time periods, such as 15 seconds, 20 seconds, 30 seconds, and the like.

Optionally, the various embodiments of the refrigerators disclosed include at least one temperature sensor 390 coupled to the controller 380. The at least one temperature sensor 390 is configured to generate a temperature signal representative of a temperature within the storage compartment 320. The controller 380 is further configured to receive the temperature signal and to operate at least one of the first cooling circuit 340 and the second cooling circuit 350 in response to the temperature signal received from the temperature sensor 390. In some embodiments, the temperature sensor 390 may be multiple temperature sensors that are positioned in differing locations within the storage compartment 320. In these embodiments, the controller may take action based upon some or all of the temperature sensors, such as to control based upon an average temperature from multiple sensors, a weighted average, or a lowest or highest reading of all of the temperatures sensors, or based upon instructions from the user about which (or which group) of temperature sensors should be controlled upon.

The use of a dual mode air screen refrigerator is explained with respect to FIGS. 3-6, which illustrates an embodiment of a refrigerator 210 that is similar in all respects to the refrigerators 10, 110. The refrigerator 210 includes a plurality of sides 215 and a door 230, along with the other components indicated in refrigerators 10, 110 that are not labeled in FIG. 2.

The refrigerator 210 is configured to operate in a single mode, as illustrated in FIG. 3, when the door 230 is closed, during which the first cooling circuit 140 (FIG. 2) is configured to operate. The refrigerator 210 is configured to operate in a dual mode, as illustrated in FIG. 4, when the door 230 is open, during which the first cooling circuit 140 and the second cooling circuit 150 (FIG. 2) is configured to operate.

The refrigerator 210 may include a door switch 234, seen in FIGS. 4 and 6, configured to generate an open signal representative of an open state of the at least one door 230 and a closed signal representative of a closed state of the at least one door 230. The door switch 234 may be a contact switch with a subcomponent 238 coupled to the refrigerator 210 along one of the sides 215 and another subcomponent 236 coupled to the door 230. Of course, other electrical and electro-mechanical switches can be used.

The refrigerator 210 also optionally includes at least one tray 238 that can be slidably withdrawn from and inserted into the storage compartment 220 along at least one guide 239. Of course, the storage compartment 220 may include any assortment of trays, bins, racks, and smaller storage compartments within the storage compartment 220.

As previously mentioned, in the dual mode operation the second cooling circuit 150 (FIG. 2) is fluidly coupled to at least one outlet vent 260 (FIG. 5) and/or to at least one inlet vent 270 (FIGS. 4 and 5) set within a perimeter 224 of the opening 222 to the storage compartment 220. In some embodiments, the second cooling circuit 150 draws cool air from within the storage compartment 220 via an air screen inlet vent 274—which is otherwise similar to the at least one inlet vent 270 but for being positioned within the storage compartment 220—and expels the cool air through the at least one outlet vent 260. During operation, air cooled and transmitted from the second cooling circuit 150 is expelled via the at least one outlet vent 260 in an air flow direction 268 towards the at least one inlet vent 270, which receives at least a part or a portion of the expelled air. The air flow in direction 268 creates an air screen that at least partially insulates the storage compartment 220 during that time when the door 230 is open. In other words, the air flow in direction 268 at least partially prevents warmer ambient air from entering the storage compartment 220 when the door 230 is open, but is not used when the door 230 is closed in order to save energy. The air screen and operation of the second cooling circuit 150 operates at a reduced energy load as calculated over a day than would otherwise be required were only the first cooling circuit 140 present to maintain an interior temperature of the storage compartment 220 both when the door 230 was closed and when it was opened. For example, conventional refrigerators with air screen functionality often include a compressor with a ¾ hp motor, while in some embodiments, the compressor for the first cooling circuit may operate with a ⅜ hp motor with the door shut, and the compressor for the second cooling circuit may operate with a second ⅜ hp motor when called for with the door open.

Optionally, the at least one outlet vent 260 is set substantially opposite from the at least one inlet vent 270 within the perimeter 224 of the opening 222, as illustrated in FIG. 4. Of course, the outlet vent 260 and the inlet vent 270 may be positioned in any relative orientation around the perimeter 224 of the opening 222.

Furthermore, the at least one outlet vent 260 optionally includes a plurality of outlet vents (not illustrated) positioned within the perimeter 224 of the opening 222 and the at least one inlet vent 260 includes a plurality of inlet vents within the perimeter 224 of the opening 222, as illustrated in FIG. 4.

The refrigerator 210 optionally includes at least one additional outlet vent 262 set inwardly, or towards the interior of the storage cabinet 220, from the at least one outlet vent 260 set within the perimeter 224, as illustrated in FIG. 5. Likewise, the refrigerator 210 optionally includes at least one additional inlet vent (not illustrated) set inwardly from the at least one inlet vent 270 set within the perimeter 224 of the opening 222. As illustrated, the at least one additional outlet vent 262 and at least one additional inlet vent may be set within the storage compartment 220 within at least one of the plurality of sides 215, whether that is along the sides, top, front, bottom, or back of the storage compartment 220. In addition, the at least one additional outlet vent 262 optionally is set in one of the plurality of sides 215 substantially opposite from the at least one additional inlet vent set in another of the plurality of sides, although the additional outlet vents 262 and additional inlet vents may be oriented relative to each other in any desired manner.

While the at least one outlet vent 260 and the at least one inlet vent 270, and any additional outlet vents 262 and inlet vents, are illustrated in FIGS. 4 and 5 as being holes, the various outlet vents and inlet vents may additionally or alternatively be in other shapes, such as slots of one or more orientations, screens, and other geometric shapes (e.g., rectangles, squares, etc.).

As mentioned above, operating embodiments of the disclosed refrigerators in a single mode and a dual mode may provide significant energy efficiencies. For example, a method includes obtaining a disclosed refrigerator, operating the first cooling circuit in the single mode when the at least one door is closed, and operating the first cooling circuit and the second cooling circuit in the dual mode when the at least one door is open.

Some of these energy efficiencies may be calculated by conducting a test procedure as set forth in Title 10 US Code of Federal Regulations Section 431.66—Appendix B (2016), as previously incorporated by reference.

For example, the method may include maintaining an integrated average temperature of the storage compartment at 38 degrees Fahrenheit plus or minus 2 degree Fahrenheit. While maintaining the integrated average temperature, the consumption of a maximum daily amount of energy in kilowatt-house per day may be established for the following conditions:

(a) consuming a maximum daily amount of energy in kilowatt-hours per day less than or equal to (0.1×a volume of the storage compartment+0.86), wherein the at least one door is vertically closed and transparent;

(b) consuming a maximum daily amount of energy in kilowatt-hours per day less than or equal to (0.05×a volume of the storage compartment+1.36), wherein the at least one door is vertically closed and solid;

(c) consuming a maximum daily amount of energy in kilowatt-hours per day less than or equal to (0.06×a volume of the storage compartment+0.37), wherein the at least one door is horizontally closed and transparent; and,

(d) consuming a maximum daily amount of energy in kilowatt-hours per day less than or equal to (0.1×a volume of the storage compartment+0.86), wherein the at least one door is horizontally closed and solid.

In the event that the refrigerator performs as or is a freezer, the method may include maintaining an integrated average temperature of the storage compartment at 0 degrees Fahrenheit plus or minus 2 degree Fahrenheit. While maintaining the integrated average temperature, the consumption of a maximum daily amount of energy in kilowatt-house per day may be established for the following conditions:

(a) consuming a maximum daily amount of energy in kilowatt-hours per day less than or equal to (0.29×a volume of the storage compartment+2.95), wherein the at least one door is vertically closed and transparent;

(b) consuming a maximum daily amount of energy in kilowatt-hours per day less than or equal to (0.22×a volume of the storage compartment+1.38), wherein the at least one door is vertically closed and solid;

(c) consuming a maximum daily amount of energy in kilowatt-hours per day less than or equal to (0.08×a volume of the storage compartment+1.23), wherein the at least one door is horizontally closed and transparent; and,

(d) consuming a maximum daily amount of energy in kilowatt-hours per day less than or equal to (0.06×a volume of the storage compartment+1.12), wherein the at least one door is horizontally closed and solid.

It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present invention and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims. 

What is claimed is:
 1. A refrigerator comprising: a plurality of sides configured to define a storage compartment; at least one opening in at least one of the plurality of sides, the opening being configured to provide access to the storage compartment, the opening being defined by a perimeter; at least one outlet vent and at least one inlet vent set within the perimeter of the opening; at least one door adapted to open and to close to provide access to the storage compartment via the at least one opening; a first cooling circuit that includes at least a first compressor, the first cooling circuit being fluidly coupled to at least the storage compartment; a second cooling circuit that includes at least a second compressor, the second cooling circuit being at least fluidly coupled to at least one of the at least one outlet vent, the at least one inlet vent, and the at least one air screen inlet vent; a door switch configured to generate an open signal representative of an open state of the at least one door and a closed signal representative of a closed state of the at least one door; and, a controller coupled to the door switch, the first cooling circuit, and the second cooling circuit, the controller being configured to (a) operate the first cooling circuit when the controller receives the closed signal and to (b) operate the first cooling circuit and the second cooling circuit when the controller receives the open signal.
 2. The refrigerator of claim 1, wherein the controller is configured to wait a period of time after the controller receives the open signal before the controller operates the first cooling circuit and the second cooling circuit.
 3. The refrigerator of claim 2, wherein the period of time is configured to be adjustable.
 4. The refrigerator of claim 1, wherein the at least one outlet vent is set substantially opposite from the at least one inlet vent within the perimeter of the opening.
 5. The refrigerator of claim 1, wherein the at least one outlet vent includes a plurality of outlet vents positioned within the perimeter of the opening and the at least on inlet vent includes a plurality of inlet vents within the perimeter of the opening.
 6. The refrigerator of claim 1, further comprising at least one additional outlet vent set inwardly from the at least one outlet vent set within the perimeter and at least one additional inlet vent set inwardly from the at least one inlet vent set within the perimeter.
 7. The refrigerator of claim 6, wherein the at least one additional outlet vent and at least one additional inlet vent are set within the storage compartment within at least one of the plurality of sides.
 8. The refrigerator of claim 7, wherein the at least one additional outlet vent is set in one of the plurality of sides substantially opposite from the at least one additional inlet vent set in another of the plurality of sides.
 9. The refrigerator of claim 1, wherein at least one of the at least one outlet vent and the at least one inlet vent is in a shape of one of a slot and a hole.
 10. The refrigerator of claim 1, wherein the second cooling circuit is coupled to the at least one outlet vent and at least one of the at least one air screen inlet vent the at least one inlet vent.
 11. The refrigerator of claim 1, wherein at least one of the first cooling circuit and the second cooling circuit further comprises at least one evaporator and at least one fan.
 12. The refrigerator of claim 11, wherein the at least one evaporator is positioned on a top side of the plurality of sides and at least one of the at least one first compressor and the at least one second compressor is positioned below the storage compartment.
 13. The refrigerator of claim 1, further comprising at least one temperature sensor coupled to the controller, the at least one temperature sensor being configured to generate a temperature signal representative of a temperature within the storage compartment, wherein the controller is further configured to receive the temperature signal and to operate at least one of the first cooling circuit and the second cooling circuit in response to the temperature signal.
 14. The refrigerator of claim 1, when the first cooling circuit is in a parallel configuration relative to the second cooling circuit.
 15. A refrigerator configured to operate in a single mode and in a dual mode, the refrigerator comprising: a plurality of sides configured to define a storage compartment; at least one opening in at least one of the plurality of sides, the opening being configured to provide access to the storage compartment; at least one outlet vent configured to expel air across the at least one opening towards at least one inlet vent configured to receive at least a portion of the expelled air; at least one door adapted to open and to close to provide access to the storage compartment via the at least one opening; a first cooling circuit that includes at least a first compressor, at least a first evaporator, and at least a first fan, the first cooling circuit being fluidly coupled to at least the storage compartment; a second cooling circuit that includes at least a second compressor, at least a second evaporator, and at least a second fan, the second cooling circuit being at least fluidly coupled to at least one of the at least one outlet vent, the at least one inlet vent, and the at least one air screen inlet vent; and, wherein the refrigerator is configured to (a) operate in the single mode when the at least one door is closed during which the first cooling circuit is configured to operate and to (b) operate in the dual mode when the at least one door is open during which the first cooling circuit and the second cooling circuit is configured to operate.
 16. The refrigerator of claim 15, further comprising a controller coupled to the first cooling circuit and the second cooling circuit, the controller being configured to operate the first cooling circuit in the single mode and to operate the first cooling circuit and the second cooling circuit in the dual mode.
 17. The refrigerator of claim 16, further comprising a door switch coupled to the controller, the door switch being configured to generate an open signal representative of an open state of the at least one door and a closed signal representative of a closed state of the at least one door, wherein the controller is further configured to operate the refrigerator in the single mode and in the dual mode in response to the closed single and to the open signal, respectively.
 18. The refrigerator of claim 15, further comprising at least one temperature sensor coupled to the controller, the at least one temperature sensor being configured to generate a temperature signal representative of a temperature within the storage compartment, wherein the controller is further configured to receive the temperature signal and to operate at least one of the first cooling circuit and the second cooling circuit in response to the temperature signal.
 19. A method of operating a refrigerator in a single mode and a dual mode, comprising: obtaining the refrigerator, which includes: a plurality of sides configured to define a storage compartment, at least one opening in at least one of the plurality of sides, the opening being configured to provide access to the storage compartment; at least one outlet vent configured to expel air across the at least one opening towards at least one inlet vent configured to receive at least a portion of the expelled air; at least one door adapted to open and to close to provide access to the storage compartment via the at least one opening; a first cooling circuit that includes at least a first compressor, at least a first evaporator, and at least a first fan, the first cooling circuit being fluidly coupled to at least the storage compartment; a second cooling circuit that includes at least a second compressor, at least a second evaporator, and at least a second fan, the second cooling circuit being at least fluidly coupled to the at least one outlet vent and to the at least one inlet vent; operating the first cooling circuit in the single mode when the at least one door is closed; and, operating the first cooling circuit and the second cooling circuit in the dual mode when the at least one door is open.
 20. The method of claim 19, further comprising: maintaining an integrated average temperature of the storage compartment at 38 degrees Fahrenheit plus or minus 2 degree Fahrenheit; and one of the following: (a) consuming a maximum daily amount of energy in kilowatt-hours per day less than or equal to (0.1×a volume of the storage compartment+0.86), wherein the at least one door is vertically closed and transparent; (b) consuming a maximum daily amount of energy in kilowatt-hours per day less than or equal to (0.05×a volume of the storage compartment+1.36), wherein the at least one door is vertically closed and solid; (c) consuming a maximum daily amount of energy in kilowatt-hours per day less than or equal to (0.06×a volume of the storage compartment+0.37), wherein the at least one door is horizontally closed and transparent; and, (d) consuming a maximum daily amount of energy in kilowatt-hours per day less than or equal to (0.1×a volume of the storage compartment+0.86), wherein the at least one door is horizontally closed and solid.
 21. The method of claim 20, wherein the steps of maintaining and consuming are performed according to a test procedure set forth in Title 10 US Code of Federal Regulations Section 431.66—Appendix B (2016). 